IDP Custom Logout

[On5-Repos]

Describe the bug
IDP logout (custom) as per defined in documentation.

$as = new Simple('myauthinstance');
$as->logout([
'ReturnTo' => 'xxxxxxxxxxxx',
'ReturnStateParam' => 'LogoutState',
'ReturnStateStage' => 'MyLogoutState'
]);
Session::getSessionFromRequest()->cleanup();

Redirect happens as per configuration but when user manually sent a call. (SP is bookmarked) IDP still consider the user is logged in and Responds back to SP request with a SAML token.

Log file shows the following:
Jun 20 09:46:37 saml DEBUG [6efd4c9e77] Session: 'myauthinstance' not valid because we are not authenticated.
Jun 20 09:46:37 saml DEBUG [6efd4c9e77] Saved state: '_a29e3b12ad9fd35ec16aabf882d916b865f89b3323'
Jun 20 09:46:37 saml DEBUG [6efd4c9e77] Session: 'myauthinstance' not valid because we are not authenticated.

To Reproduce (create custom route)
public function customLogout(Request $request)
{

if ($this->config->getBoolean('enable.saml20-idp') === false || !Module::isModuleEnabled('saml')) {
  throw new Error\Error('NOACCESS', null, 403);
}

$as = new Simple('myauthinstance');
$as->requireAuth();
$as->logout([
  'ReturnTo' => 'xxxxxxxxxxx',
  'ReturnStateParam' => 'LogoutState',
  'ReturnStateStage' => 'MyLogoutState'
]);
Session::getSessionFromRequest()->cleanup();

}

After login just browse to URL ....